The fall lasts long enough that I have time to watch the blue ice race upward, aeons of time compressed into glacial ice, flashing by in fractions of seconds. I assume I’ve fallen far enough that I’ve pulled my climbing partner, Sean, into the crevasse with me. This is what it’s like to die in the mountains, a voice in my head tells me.

Just as my mind completes that thought, the rope wrenches my climbing harness up. I bounce languidly up and down as the dynamic physics inherent in the rope play themselves out. Somehow Sean has checked my fall while still on the surface of the glacier.

I brush the snow and chunks of ice from my hair, arms and chest and pull down the sleeves of my shirt. Finding my glacier glasses hanging from the pocket of my climbing bib, I tuck them away. I check myself for injuries and, incredibly, find none. Assessing my situation, I find there’s no ice shelf nearby to ease the tension from the rope, so Sean will not be able to begin setting up a pulley system to extract me.

I look down. Nothing but blackness. I look at the wall of blue ice directly in front of me, take a deep breath and peer up at the tiny hole I made when I fell through the snow bridge spanning the crevasse – the same bridge Sean had crossed without incident as we made our way up Alaska’s Matanuska Glacier towards Mount Marcus Baker in the Chugach Range.

“You get to look down one more time, then that’s it,” I tell myself out loud.

“Sean, are you OK?” I yell as I clamp my mechanical ascenders to the rope in preparation to climb up.

“Yeah, I’m all right, but I’m right on the edge,” he calls back. “I can’t set up an anchor, so we’re just going to have to wait for the other guys to catch up.”

Time passes. The onset of hypothermia means I can’t control my body from periodically shaking. To ignore my fear of dying, I gaze meditatively at the ice a few feet in front of me as I dangle.

The miniature air pockets found in the whiter ice near the top of the glacier have long since been compressed, producing the mesmerising beauty of centuries-old turquoise ice. Slightly deeper into the crevasse is ice that has been there since long before the Neanderthals.

I hang suspended in silence, mindful not to move for fear of dislodging Sean. Giving my full attention to the ice immediately within my vision, I focus on how the gently refracting light from above seems to penetrate and reflect off the perfectly smooth wall. Staring into it, the blue seems infinite. Despite the danger of my situation, the glacier’s beauty calms me.

Eventually our two other teammates arrive and work to extract Sean from his perch just six inches from the edge of the crevasse. The three of them set up a three-way pulley system. Laboriously, my teammates begin to haul me up, inches at a time, out of what nearly became my tomb. I continue to focus on the delicately shifting shades of blue in the ice as I draw closer to the surface.

My teammates pull me up to the lip of the crevasse. I repeatedly plunge the pick of my ice axe into the snow and haul myself out, never before as grateful for being on top of a glacier. I stand and gaze up at a mountain to the west, behind which the sun has just set. Snow plumes stream off one of its ridges, turned into red ribbons by the setting sun. Snowflakes flicker as they float into space.

As relief floods my shivering body, I roar in gratitude. Utterly overwhelmed by being alive and surrounded by the beauty of the mountain world, I hug each of my three climbing partners. Now that I am safe, it sinks in just how close to death I’ve been.

That was 22 April 2003 – Earth Day. In hindsight, I believe the emotion I felt then stemmed in part from something else – a deeper consciousness that the ice I had seen was vanishing. Seven years of climbing in Alaska had provided me with a front-row seat from where I could witness the dramatic impact of human-caused climate disruption. Each year, we found that the toe of the glacier had shrivelled further. Each year, for the annual early season ice-climbing festival on this glacier, we found ourselves hiking further up the crusty frozen mud left behind by its rapidly retreating terminus. Each year, the parking lot was moved closer to the glacier, only to be left farther away as the ice withdrew. Even sections of Denali – the highest mountain in North America, which stands more than 20,000 feet tall and is roughly 250 miles from the Arctic Circle – had already undergone startling changes in 2003: the ice of its glaciers was disappearing quickly.

Our planet is rapidly changing, and what we are witnessing is unlike anything that has occurred in human, or even geological, history. The heat-trapping nature of CO2 and methane, both greenhouse gases, has been scientific fact for decades, and according to Nasa, “no question that increased levels of greenhouse gases must cause the Earth to warm in response”. Evidence shows that greenhouse gas emissions are causing the Earth to warm 10 times faster than it should, and the ramifications of this are being felt, quite literally, throughout the entire biosphere.

Oceans are warming at unprecedented rates, droughts and wildfires of increasing severity and frequency are altering forests around the globe, and the Earth’s cryosphere – the parts of the Earth so cold that water is frozen into ice or snow – is melting at an ever-accelerating rate. The subsea permafrost in the Arctic is thawing, and we could experience a methane “burp” of previously trapped gas at any moment, causing the equivalent of several times the total amount of CO2 humans have emitted to be released into the atmosphere. The results would be catastrophic.

Climate disruption also brings with it extreme weather such as hurricanes and floods. For instance, a warmer atmosphere holds more moisture, leading to an increase in the frequency of severe major rain events, such as Hurricane Harvey over Houston in summer 2017, which dropped so much rain that the weight of the water actually caused the Earth’s crust to sink by 2cm.

Earth has not seen current atmospheric CO2 levels since the Pliocene epoch, some 3m years ago. Three-quarters of that CO2 will still be here in 500 years. It takes a decade to experience the full warming effects of CO2 emissions. Even if we stopped all greenhouse gas emissions, it would take another 25,000 years for most of what is currently in the atmosphere to be absorbed into the oceans.

A glacial pool in Denali national park and preserve in Alaska. Photograph: Aaron Huey

Climate disruption is progressing faster than ever, and faster than predicted. Seventeen of the 18 hottest years ever recorded have occurred since 2001. The distress signals from our overheated planet are all around us, with reports, studies and warnings increasing daily. Worst-case prediction made by the Intergovernmental Panel on Climate Change about the rise in temperatures, extreme weather, sea levelsandCO2 levels in the atmosphere have fallen short of reality. Countless glaciers, rivers, lakes, forests and species are already vanishing at a pace never seen before, and all of this from increasing the global mean temperature by “only” 1C above the preindustrial baseline. Some scientists predict it could rise by as much as 10C by 2100. A study led by James Hansen, the former director of Nasa’s Goddard Institute for Space Studies, warned that the rise we have seen so far has already caused unstoppable melting in both the Antarctic and Greenland ice sheets.

Mountaineering in today’s climate-disrupted world is a vastly different endeavour from what it used to be. Glaciers are vanishing before our eyes, having shrunk to the lowest levels ever recorded, and are now melting faster than ever. Seventy per cent of the glaciers in western Canada are projected to be gone by 2100. Montana’s Glacier National Park will most likely not have any active glaciers by 2030. The Matanuska Glacier’s ancient ice is already rapidly vanishing. Dramatic changes are occurring even in the planet’s highest and coldest places. Even Mount Everest is transforming, as thousands of glaciers across the Himalayas are likely to shrink by up to 99% by 2100. A child born today will see an Everest largely free of glaciers within their lifetime.

I lived in Alaska for a decade beginning in 1996, and spent time on the glaciers there. As early as the late 90s, large portions of the holiday season would go by in Anchorage without any snow on the ground. The waterfalls that my climbing friends and I had used for ice climbing barely froze some winters, and we could see the glaciers that we used to traverse to access peaks shrinking from year to year.

In Nepal the sacred mountain Machapuchare rises abruptly on the eastern boundary of the Annapurna Sanctuary. As a child I came across a photograph of this peak in a geography textbook and was immediately captivated by its majesty. Shaped like a fish’s tail, the knife-edged ridge that forms its summit is a seemingly paper-thin line of rock that drops precipitously on either side, causing the apex of the peak – which is nearly half a mile higher than the top of Denali – to be one of the more dramatic summits anywhere. It is a masterpiece of nature.

When I was 10 years old, I saw the Rocky Mountains of Colorado for the first time, their silhouettes against the setting sun, and I was awestruck. Years later I travelled to Alaska and drove a short way into Denali national park and preserve. When the afternoon clouds parted to reveal the majesty of Denali’s summit, my first inclination was to bow in wonderment. A year after that I moved to Alaska, and began training myself in the mountaineering skills I needed to access these sanctuaries that stand far from the violence, speed and greed of society. John Muir, the Scottish-American naturalist, author, philosopher and early wilderness-preservation advocate, captured my feelings precisely: “I am losing precious days. I am degenerating into a machine for making money. I am learning nothing in this trivial world of men. I must break away and get out into the mountains to learn the news.”

A glacier is essentially suspended energy, suspended force. It is, in a sense, life frozen in time. But now they are themselves running out of time. The planet’s ecosystems, pushed far beyond their capacity to adapt to human-generated traumas and stresses, are in a state of freefall. Just as I watched hundreds of years of time compressed into glacial ice flash before my eyes in a matter of seconds as I fell into the crevasse, swathes of the natural world are, in the blink of a geological eye, falling into oblivion.

Modern life has compressed time and space. You can traverse the globe in a matter of hours, or gain information in nanoseconds. The price for this, along with everything we want, on demand, all the time, is a total disconnection from the planet that sustains our lives.

I venture into the wilds and into the mountains in large part to allow space and time to stretch themselves back to what they were. The frenetic pace of contemporary life is having a devastating impact on this planet. Humans have transformed more than half the ice-free land on Earth. We have changed the composition of the atmosphere and the chemistry of the oceans from which we came. We now use more than half the planet’s readily accessible freshwater runoff, and the majority of the world’s major rivers have been either dammed or diverted.

As a species, we now hang over the abyss of a geoengineered future we have created for ourselves. At our insistence, our voracious appetite is consuming nature itself. We have refused to heed the warnings Earth has been sending, and there is no rescue team on its way.

At the end of July 2017 I flew to Alaska’s northern shore. A couple of days after my arrival I took a morning walk along the Arctic Ocean. The only thing that was a constant was the shore beneath my boots and the crunching sound of the tiny stones as I walked. Up here, only 1,300 miles from the north pole, the sun never sets in summer, and time stretches until it loses its meaning.

Utqiagvik (formerly known as Barrow), one of several ancient villages in the area, is the northernmost incorporated point in the US. The indigenous people here, the Iñupiat, have learned to live on the edge of the tundra and the seas, with the whales, the birds and the ice floes.

I met 55-year-old Marvin Kanayurak, who was born and raised here, as were his parents. He is a whaler and volunteers doing rescues. He tells me how there used to be pressure ridges in the sea ice (formed when two ice floes are forced together) during the winter that were 50 or even 60 feet high, but now they are “lucky” to find any even 20 feet tall. Heading out across the ice to find open water in the spring used to take them two weeks of plotting and making a trail. Now it takes them only a couple of days because the open water is so much closer.

Kanayurak had told me that he was a volunteer gravedigger. The permafrost used to be 10-12 inches below the surface, so it would take three days of chipping with an ice pick to dig a grave. Now the permafrost is several feet below the surface, and softer, so he can dig a grave in a few hours.

Permafrost is a layer of ground that is continuously frozen for a period of two years or more. It contains dead plants that absorbed CO2 from the atmosphere centuries ago, and then froze before decomposing. When it thaws, microbial activity converts a large portion of that organic material into methane and CO2, which is released back into the atmosphere. According to a Nasa report, over hundreds of millennia, “Arctic permafrost soils have accumulated vast stores of organic carbon” – an estimated 1,400-1,850 gigatonnes, compared to 850 gigatonnes of carbon in Earth’s atmosphere.

That’s equal to around half of all the estimated organic carbon in Earth’s soils, with most of it located in the top 10 feet of thaw-vulnerable soil. Scientists, along with others, are learning that the Arctic permafrost is less permanent than its name implies. Estimates of how much carbon will be released by thawing permafrost show it could average around 1.5bn tonnes annually, which is roughly the same amount as current US annual emissions from burning fossil fuels. Dr Kevin Schaefer, a research scientist for the National Snow and Ice Data Center who studies permafrost carbon feedback (PCF) – the warming of the surface of the planet that would result from the release of carbon from the permafrost – estimates that PCF by itself will increase temperatures by 0.2C by 2100, and even more beyond that. This means PCF will have a significant effect on the long-term climate, even if the goal of limiting atmospheric temperatures to 2C is reached.

A climber jumps over a glacial stream on the Ruth Glacier in Denali national park. Photograph: Aaron Huey

While I was in Utqiagvik I spoke to Dr Vladimir Romanovsky, a professor of geophysics at the University of Alaska Fairbanks, who also specialises in permafrost. His lab has been collecting temperature data each year in many locations around the world, but mostly across Alaska, Canada and Russia.

“If it comes closer to thawing point, then it becomes unstable,” Romanovsky said. “For any permafrost research, that is the crucial data: what is the temperature and how stable is it?”

His lab is unique in that it now has nearly 40 years of data records from a variety of locations, and he generates permafrost temperature modelling to explain how the temperatures are changing.

The changes in the permafrost happening across Alaska’s North Slope are due to some of the most dramatic temperature increases in the world. In 35 years of measurements here, the temperature at 20 metres below the ground has increased by 3C since Romanovsky’s first measurement, and at the surface of the permafrost one metre below the ground, the average temperature has increased by a staggering 5C since the mid-1980s. Even small increases bring the temperature of the permafrost closer to 0C. Crossing that line means the permafrost will start to thaw.

Scientists used to believe the permafrost was stable across the North Slope, and that it would not begin to thaw this century. Romanovsky said: “If you look at our records, however, and extrapolate into the future another 30 years, assuming changes continue as they have been for the last 30 years, the permafrost on the North Slope will hit 0C by 2050 or 2060 at the latest. Nobody was expecting this, and most people would be surprised to see this happen so soon.”

Schaefer also expressed concern about the impact that thawing permafrost will have on the infrastructure and people of the Arctic. “Thawing permafrost represents a radical change to the environment and way of life in the Arctic, with unknown social costs,” he said. I asked if he thought it would be necessary to relocate most, if not all, of the coastal villages in northern Alaska. He said that as sea levels go up and permafrost thaws, “there is risk the thawing will destroy critical infrastructure, which will require repair or moving it, and that includes entire villages. If you built your village right next to the ocean and it starts to melt, you have to move. This is happening in interior Alaska along rivers, and it’s also happening across the entire Arctic zone.”

Roads, railroads, oil and gas infrastructure, airports, seaports – all these things were built across the Arctic on the assumption that the permafrost would stay frozen. “When it is frozen it is solid, but it thaws out and turns to mud, so it’s easy to see this causing a lot of damage to infrastructure,” Schaefer said.

Dr Leonid Yurganov, a senior research scientist at the University of Maryland Baltimore County physics department and the Joint Center for Earth Systems Technology, is an expert in the remote sensing of Arctic methane levels. He told me his team of researchers had already detected long-term increases in methane over large areas of the Arctic, and warned that the fast liberation of methane would influence air temperature near the surface and accelerate Arctic warming. “The difference in temperatures between the poles and the equator drives our air currents from west to east,” he said. “If this difference diminishes, the west-to-east air transport becomes slower, and north-south air currents become stronger. This results in frequent changes in weather in the midlatitudes.”

It would change the climate, he says, “everywhere in the world”.

Two days after leaving Utqiagvik, I flew from Anchorage to Seattle on my way home. Forty-five minutes before we landed, while flying at 35,000 feet, the plane entered a cloud of brownish-grey smoke rising from the 146 wildfires scorching British Columbia beneath us. At that point, they had burned more than 600,000 acres and forced 7,000 people from their homes. We descended into the brown cloud until we landed in Seattle, which was also enveloped in the smoke.

A couple of days later, a leaked draft report from US scientists across 13 federal agencies warned of a worst-case scenario of 18F warming over the Arctic between 2071 and 2100. The report also noted that the Arctic was losing more than 3.5% of its sea ice coverage every decade, that the extent of the September sea ice had declined more than 10% per decade, that the land ice was disappearing at an increasingly rapid rate and that the severity of winter storms was increasing because of warming temperatures.

The grim news seemed endless: the snow-free season on Alaska’s North Slope is lengthening. The year 2016 experienced the longest snow-free season in 115 years of record-keeping – roughly 45% longer than the average snow-free period over the previous four decades. The October temperature at Utqiagvik increased by a staggering 7.2C between 1979 and 2012.

We are already facing mass extinction. There is no removing the heat we have introduced into the oceans, nor the 40bn tons of CO2 we pump into the atmosphere every single year. There may be no changing what is happening, and far worse things are coming. How, then, shall we meet this?

Like so many people, I have wondered what to do at this time. Each of us now must find our own honest, natural response to the conditions that we have brought upon ourselves.

I am heartened by people like my friend Karina Miotto in Brazil, who has devoted her entire life to protecting the Amazon. Each time a report is published about increased deforestation in her beloved rainforest, I watch Karina become consumed in grief. But each time, she goes deeper within herself and her community, further strengthening her love for that portion of the planet where she lives, and repurposes herself into her next action to protect the Amazon. I find solace in the fact that there are millions of others like Karina, particularly among the younger generations, who have drawn their lines around their respective portions of the planet closest to their hearts and are making their stands.

How climate scepticism turned into something more dangerous

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I find my deepest conviction and connection to the Earth by communing with the mountains. I moved to Colorado and lived among them when I was in my early 20s, and it was there I began to deepen my relationship with them, and to really listen to them. I would hike out and just sit among the peaks, watching them for hours, and write about them in my journal. Today I know in my bones that my job is to learn to listen to them ever more deeply, and to share what they are telling us with those who are also listening.

While western colonialist culture believes in “rights”, many indigenous cultures teach of “obligations” that we are born into: obligations to those who came before, to those who will come after, and to the Earth itself. When I orient myself around the question of what my obligations are, a deeper question immediately arises: from this moment on, knowing what is happening to the planet, to what do I devote my life?

This is an edited extract from The End of Ice by Dahr Jamail, which will be published by The New Press on 15 January

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